Chapter 2 Flashcards
(11 cards)
3 stages of prenatal development
1.Germinal Stage
Weeks 1 and 2
Begins with conception
2.Embryotic Stage
Weeks 3 to 8
Not a recognizable human
- Fetal stage
Weeks 9 to birth
Umbilical cord and placenta transfer nutrients
Developmental processes
- cell division (12 hours after conception)
- cell migration (go to diff area in the body)
- cell differentiation (specialize in development)
- cell death
- Hormones
Fetal Behaviour
Movement - by 5 to 6 weeks
Fetal experience : tactile stimulation
Fetal Learning
Habituation
-decrease in response to continues stimuli
-change in stimuli - fetus responds
Ex : increase in heartbeat, diff suckling
By 7 months CNs is developed enough for learning- learning the sound of mothers voice
Teratogens
Definition and 4 examples
Any environmental agents that can interfere with the process of normal development.
- Medical Drugs Ex: Thalidomide (morning sickness)
- Maternal Illness Ex: Rubella (Measels)
- Legal Drugs (alcohol, smoking)
- Illegal Drugs(cocaine, weed)
Principles of Environmental Influence( 9 principles)
- The placenta is not an effective barrier against harmful substances
- critical period
- Genes x Environment
- Different teratogens can produce the same effect
- A single teratogen can produce multiple defects
- greater the exposure more the harm
- Physical and behavioural effects
- Effects may not be obvious at birth
- importance of post natal care
Why is the fetus more affected than the mother
- Dose Effects
- organogenesis
- Immature liver
Maternal Risk Factors (4)
- Nutrition
- Adolescent Pregnancy
- Pregnancy after 35
- Emotional states
Fetal alcohol syndrome effects
- Growth retardation(small head, flattened features)
- Developmental delays
- Intellectual impairment
- Behavioural problems
- Attention deficit - learning problems
Smoking
Risk of miscarriage
Risk of premature death
Risk of sudden infant death
Infant mortality risk factors
Poverty, health care access, environmental stressors, famine , war
-low birth weight
